We propose to improve the chemistry of novel gels developed under the Phase I SBIR Grant under this project. Novel crosslinking agents will be developed. Currently our 0.1% gels are at least as strong as 0.4% standard agarose gels. Improvements in gel chemistry are expected to more than double the gel strength. These improvements are also designed to overcome the charge problems that currently appear to retard DNA. We expect to be able to resolve up to 150 kbp DNA in less than 30 Vh/cm in a 0.1% gel, down from the present 60 Vh/cm, by constant field gel electrophoresis. Using field inversion and other pulsed field gel electrophoresis techniques, we will characterize the approximate upper limits of resolvable DNA sizes, theoretically expected to be about 50 Mbp for a 0.1% gel. Gels will be characterized for post-electrophoretic manipulations, such as a: DNA recovery; b) enzymatic manipulation of DNA in gel or after recovery;4,c) DNA transfer to membrane and subsequent detection and, d) in-gel DNA hybridization. Production of product formats kit or pre-cast gels), packaging, shelf life, and transportability.